Questions 71–80 of 83. Imported answers require independent review unless marked reviewed.

Topic practice 83 questionsPage 8 of 9

Question 15

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The intrinsic/permanent electric dipole moment in the ground state of hydrogen atom is (

is the Bohr radius)
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Question 31

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If

is the Hamiltonian for a free particle with mass

, the commutator

is
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Question 47

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The ground state energy of a particle of mass

in an infinite potential well is

. It changes to

, when there is a small potential bump of height

and width

, as shown in the figure.
Diagram for Physics question 47

The value of

is ______ (up to two decimal places).

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Question 50

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A two-state quantum system has energy eigenvalues

corresponding to the normalized states

. At time

, the system is in quantum state

. The probability that the system will be in the same state at

is ______ (up to two decimal places).

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Question 14

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The wavefunction of which orbital is spherically symmetric:
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Question 19

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A one dimensional simple harmonic oscillator with Hamiltonian

is subjected to a small perturbation,

. The first order correction to the ground state energy is dependent on
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Question 20

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For the Hamiltonian

where

,

is a real vector,

is the

identity matrix, and

are the Pauli matrices, the ground state energy is
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Question 22

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The degeneracy of the third energy level of a 3-dimensional isotropic quantum harmonic oscillator is
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Question 23

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The electronic ground state energy of the Hydrogen atom is

eV. The highest possible electronic energy eigenstate has an energy equal to
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Question 34

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A free electron of energy 1 eV is incident upon a one-dimensional finite potential step of height 0.75 eV. The probability of its reflection from the barrier is ________ (up to two decimal places).

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